Used to collect PDM sample data from a port. More...

#include <PdmRx.hpp>

Public Member Functions
void	SetPort (port_t p_pdm_mics)
	Set the port from which to collect PDM samples.

void	ProcessNext ()
	Perform a port read and if a new block has completed, signal.

void	ThreadEntry ()
	Entry point for PDM processing thread. More...

Static Public Attributes
static constexpr unsigned	BlockSize = BLOCK_SIZE
	Number of words of PDM data per block.

Protected Attributes
port_t	p_pdm_mics
	Port from which to collect PDM data.

unsigned	phase = BLOCK_SIZE
	Number of words left to capture for the current block.

uint32_t	block_data [2][BLOCK_SIZE]
	Buffers for PDM data blocks.

uint32_t *	blocks [2] = {&block_data[0][0], &block_data[1][0]}
	PDM block redirection pointers. More...

Detailed Description

template<unsigned BLOCK_SIZE, class SubType>
class mic_array::PdmRxService< BLOCK_SIZE, SubType >

Used to collect PDM sample data from a port.

This class is used to collect blocks of PDM data from a port and send the data to a decimator for further processing.

PdmRxService is a base class using CRTP. Subclasses extend PdmRxService providing themselves as the template parameter SubType.

This base class provides the logic for aggregating PDM data taken from a port into blocks, and a subclass is required to provide methods SubType::ReadPort() and SubType::SendBlock().

SubType::ReadPort() is responsible for reading 1 word of data from p_pdm_mics.

SubType::SendBlock() is provided a block of PDM data as a pointer and is responsible for signaling that to the subsequent processing stage. (Called from PdmRx thread or ISR)

SubType::GetPdmBlock() (called from MicArray thread) is responsible for receiving a block of PDM data from SubType::SendBlock() as a pointer, deinterleaving the buffer contents, and returning a pointer to the PDM data in the format expected by the mic array unit's decimator component.

Template Parameters

BLOCK_SIZE	Number of words of PDM data per block.
SubType	Subclass of `PdmRxService`

Member Function Documentation

◆ ThreadEntry()

template<unsigned BLOCK_SIZE, class SubType >

void mic_array::PdmRxService< BLOCK_SIZE, SubType >::ThreadEntry

Entry point for PDM processing thread.

This function loops forever, calling ProcessNext() with each iteration.

Member Data Documentation

◆ blocks

template<unsigned BLOCK_SIZE, class SubType >

uint32_t* mic_array::PdmRxService< BLOCK_SIZE, SubType >::blocks[2] = {&block_data[0][0], &block_data[1][0]}

protected

PDM block redirection pointers.

Each time a new block of data is ready, a double buffer pointer swap is performed and blocks[1] is passed to SubType::SendBlock() so that it can be signaled to the next processing stage.

The documentation for this class was generated from the following file:

/build/modules/io/modules/mic_array/lib_mic_array/api/mic_array/cpp/PdmRx.hpp

Public Member Functions

Static Public Attributes